1. Field of the Invention
This invention relates to accessing information from a computer network via a telephone, PDA equipped with an audio input/output or other portable device, speaker phone, or other audio device. More specifically, this invention relates to dynamically converting standard document formats, such as hyper-text mark-up language (HTML), standardized graphic mark-up language (SGML), Hytime, and electronic mail (E-mail), for use in an audio interface, locally or over a telephony network.
2. Discussion of the Related Technology
Voice mail and other interactive voice response (IVR) systems allow a user to access audio information stored in a computer memory such as a hard disk. Typically, the audio information is stored in audio files created either by the user or for the user. Conventional IVR systems use dual-tone multi-frequency (DTMF) signalling to allow the user to interact with the server through a standard telephone keypad. Pre-recorded audio information is available on IVR systems in the form of instructional phrases such as "Please type in your account number followed by the pound sign."
Pre-recorded audio is also used for introductory phrases such as "Your account balance is . . . " At this point, the IVR computer may access a connected database that stores the requested account balance in numerical format, convert the numerical format to an audio format using a numerical text-to-speech engine, and state the account balance. This conversion from numerical format to audio format is extremely rigid and completely predefined. IVR systems are "closed" in that each IVR system is uniquely designed, not connected to a computer network, and IVR systems cannot be used interchangeably. Also, these IVR systems are designed specifically for audio interaction.
In contrast, audio/visual information on a audio/visual server in a computer network may be accessed using a personal computer. For example, a World Wide Web (Web) page on the Internet may be accessed using a computer linked through an Internet access provider, such as America On Line.TM. or Prodigy.TM., to a Web server. In certain situations, however, use of a computer may not be feasible or access to a computer may not be possible. For example, a cellular telephone user driving an automobile may want to know about traffic in the surrounding area, however, the user cannot operate a computer while in the car. In situations such as this, an audio interface may be useful for obtaining information from the Internet or another computer network.
Other situations where an audio interface to a computer network may be useful include accessing an electronic calendar on a local area network (LAN) to receive or modify an itinerary, accessing E-mail on the Internet or a wide-area network (WAN) while away from a computer, and requesting a telephone number from an electronic yellow pages or white pages while at a pay phone. An audio interface to the Web could also be used to traverse the Internet and obtain information residing on various Web servers.
Thus, there is a need for flexible access to various types of computer networks via an audio interface. There is a need for interactive telephone access to a computer network. There is also a need for dynamic conversion of an audio/visual file format to a pure audio format.